1. Field of the Invention
This invention relates to a light emitting indicator for a camera, and particularly to a light emitting indicator for a camera which is so constructed that so long as the scene brightness is below a predetermined level, the brightness of the light emitting indicator means increases with the decrease of the scene brightness for the sake of compensation.
2. Description of the Prior Art
The performance of semiconductor devices used in the light measuring device in a camera, have been much improved so that they are increasingly sensitive to low brightness. In measuring brightness through the taking lens, which is a leading photometric technique for low scene brightness, the increasing sensitivity of the light measuring device sometimes adversely causes the setting of a period of exposure longer than can be met by the self-setting interlocking mechanism of the camera.
If the shutter is actuated in such an adverse condition, no significant pictures will be taken. When the exposure duration is set so that it takes too long a time, the person handling the camera sometimes wonders whether something is wrong with the camera. The same thing takes place if the shutter is released before the stable state has been reached because of the slow response of the light measuring circuit.
In an attempt to preclude these defects it has hitherto been proposed to connect a resistance across a photocell of the light measuring circuit. A second proposal is that the longest permissible exposure time be determined with reference to the logic sum of the output signal from the light measuring circuit and the output signal from a longest time determining circuit, which works independently of the light measuring circuit.
Connection of a resistance across the photocell has the disadvantage that the sensitivity of the light measuring circuit is badly reduced for low scene brightness. On the other hand, when the second proposal is attempted, the response speed of the light measuring circuit cannot be improved, and therefore the circuit is not stable in operation immediately after the circuit has been connected to the power supply. This is totally defective unacceptable in cameras in which the electric circuits are connected to the power supply when the shutter is released.